Cushion plow trip



Aug- 24, 1965 R. T. FULTON 3,202,223

CUSHION PLOW TRIP Filed March 2, 1964 I NVENT `and a forwardlyprojecting tool bar 12.

United States Patent C 3,202,223 CUSHHGN PLUW TREE Ronald T. Fulton,Tinley Park, Ill., assigner to international Harvester Company, Chicago,El., a corporation of New Jersey Filed Mar. 2, 1964, Ser. No. 348,740 6Claims. (Cl. 172-264) This invention relates to earth working implementsand particularly to cushion trip mechanism therefor. More specifically,the invention concerns cushion spring Itripping mechanism for amoldrboard plow.

Tripping devices for moldboard plows and the like are well known. Suchmechanism is provided to allow the plow unit to swing backwardly andupwardly when abnormal draft conditions are encountered which mightdamage the implement. Cushioning devices are usually incorporated -withthe tripping mechanism to minimize the shock to the implement whenencountering an ohstruction.

Many of the obstructions encountered by a plow bottom `during operationexert a force in a direction tending to swing the plow unit rearwardlyand upwardly until the obstruction is passed. However, particularly inrocky soil, a common yform of obstruction is a rock or the like having aplow engaging surface so disposed that, upon engagement thereof by theforward end or point of a plow bottom, it exerts a force against theplow bottom having a vertically upwardly directed component tending torevolve the plow unit in a direction opposite to the direction in whichit trips rearwardly .and upwardly. Stating the problem in another way,Iwhen facing the side of the plow, obstructions are encountered in thesoil which direct forces against the plow unit which would tend torevolve it about a pivot in both clockwise and countercloclrwisedirections.

. The present invention has for its object the provision of an improvedearth working implement incorporating therein Imeans for off-settingsubstantially all of the al normal ground forces `acting against theearth working uni-t during operatiom Another object of the invention isthe provision of an improved implement such as a moldboard plowattachment mounted on a supporting frame by means accommodating angularmovement of the front end of the plow bottom upwardly when encounteringVone type of obstruction and causing the rear end of the plow bottom toswing angularly upwardly in the other direction upon encounteringanother type of obstruction,

Another object of the invention is to provide means for mounting a plowunit .upon a supporting lframe whereby the plow unit is maintained inoperating position during normal ,operation but is permitted to swing inresponse to abnormal ground forces encountered thereby, in eitherdirection about a ltransverse axis.

Other objects and advantages of the invention will become clear yfromthe following detailed description when read in conjunction with `theaccompanying drawings wherein:

`FIGURE l shows a sectional view of a portion of a plow supporting frameupon which is mounted a moldhoard plow unit incorporating the featuresof this invention,

FIGURE 2 is a View in rear elevation of the structure shown in FIGURE l,and

FIGURE 3 is a plan View of the structures shown in FIGURES l and 2.

In the drawings the numeral 10 designates a plow support-ing frameincluding a diagonally disposed beam 11 Mounted upon the beam 111 is anearth working unit 13 including a diig Patented Aug. 24, 1965 ICCstandard 14 having a vertical section 15 upon the lower end of which ismounted a plow bottom lo having a rear or 4rnoldboard section 17 and a.forward share or point section 18. The upper end of standard 14 has aforwardly projecting upper section 19, and consists of spaced plates,the forward portions 19 of which straddle an upright Ztl affixed to beam11.

The lforward end of section 19 of the standard carries a pivot elementin the form of a pin 21 extending between the plates forming thestandard and slidable in another pivot element in the form of agenerally vertical extending slot 22 formed in the upper end of a lever23 pivotally mounted at 24 yupon the bar i12.

As shown in dotted lines in FGURE 1, standard 14 is longitudinallyslidable relative to the supporting frame 1@ in response to longitudinalshifting or rocking movement of lever 23. The rearward movement of thetool carrying standard relative to the frame is opposed by a compressionspring 25 anchored at its forward end to pivot means consisting of thepin 21 in slot 22, and at its other end to the upper end of upright 2i),'the spring 2S thus tending to yieldably maintain the plow unit in thesolid line position Iof rFlGURE .1. Spring 25 is one of a pair formingspring means which acts as a shock absorber for the plow unit 113 whenabnormal draft conditions are encountered. For example, when a rock orother obstruction is encountered by the forward end 13 of the plowbottom exerting a force in a direction downwardly against the forwardend of the bottom the plow unit tends to revolve about the axis of pivotpin 21 in a clockwise direct-ion as viewed in FIGURE l.

ln normal operating position the plow unit operates in the solid lineposition of FIGURE l. A pivot element in the forrn of a pin 26 islongitudinally spaced rearwardly of p-ivot pin 21 and is mounted betweenthe plates of standard 14, and the central .portion thereof if receivedin another pivot element in the form of a slot 27 formed in the rearedge of upright 2t! and opening rearwardly therefrom. Thus, upon theplow bottom 16 encounter-ing an obstruction of the type referred towhich tends to trip the plow unit in a clockwise direction as viewed inFIGURE l, the plow unit moves rearwardly against the action of springs25 until pin 26 is released from slot 27 and rides up the rear edge yofupright 2% in the manner indicated in dotted lines in FGURE 1.

Another type of construction frequently encountered, and itsrelationship to the point of the plow bottom, is indicated at A28 andconsists of a -rock or the like having a face over which the plow bottomtends to ride, in that the lower face of the point of the plow engagesthe obstruction and tends to be lifted thereby, exerting a forceupwardly in a direction to rock the plow counterclockwise. Until thetime of the present invention the engageent of the plow bottom with anobstruction of this type tending to lift it Iby the front end causedfrequent breakage of the plow points `as well as other damage. Thepresent invention avoids such la circumstance and prevents damage to theplow by permitting limited 'angular move- -rnent of the tool carryingstandard about the pivot axis of the rearmost pivot pin 26. Toaccomplish this, lost motion is provided in the `for-rn of the riding of.pin 21 in slot 22 of lever 23, springs 215 exerting force in adirection to hold pin 21 4at the bottom of slot 212, the upward movementof :the forward end of the plow bottom 16 by virtue of encountering `theobstruction 28 :being indicated by `dotted Llines in FIGURE -1 It isbelieved that the construction and operation of the novel plowcushioning and trip device of this invention will be clearly understoodfrom the foregoing description. it should likewise be -understood thatthe invention has been described in its preferred embodiment and that Dmodications may be made therein without departing from the spirit of theinvention or the scope ot the appended claims.

What is claimed is:

1. In ytrip plows and the like, a supporting frame member, a standardmember carrying an earth working tool at its lower end, means formounting said standard member on said frame member for longitudinalmovement of the standard member relative to the frame member, saidmounting member including pivot means accommodating swinging of saidstandard member upwardly in one direction about a transverse axis aftera predetermined iongitudinal movement ot the standard member relative tothe trame member in response to abnormal draft forces acting on the toolin said one direction, means in the mounting ot said standard member onsaid trarne mem-ber accommodating swinging ot said standard mcmlber invthe other direction about a transverse axis prior to said longitudinalmovement of the standard member relative to the `trarne member inresponse to abnormal draft torces acting on the tool in said otherdirection, and spring means operatively `connected between said framemember and said standard member for yieldably opposingsaid `swinging-ofsaid standard member.

2. `ln a cushion spring trip assembly for an implemen-t having asupporting frame including an upright member, an earth working unitmounted on the frame comprising, a tool-carrying standard including agenerally vertical section having an earth working tool at its lower endand an upper vforwardly extending generally horizontal section, meanspivotally connecting said standard to said upright member, alongitudinally shittable member mounted on the frame, means pivotallyconnecting said horizontal section to said shi-ftable member, saidshitta-ble member being shiftable rearwardly with said tool-carryingstand-ard in .response to draft forces on said tool during operation,spring means operatively connected between the frame and said shiftablemember to yieldably oppose rearward movement of said standard, meansserving as a transverse pivot connect-ing the standard to the frame, theconnection of said horizontal section to said shiftable member beingsuch as to accommodate tilting of the forward end oit said horizontalsection upwardly about said pivot when draft conditions exert a forceupwardly against the forward end of said tool.

3. The invention set forth in claim 2, wherein the connection of saidhorizontal section of the standard to said shiftable member includeslost motion accommo dating said tilting of the `forward end `of saidhorizontal section upwardly about said Ipivot.

lil, The invention set forth in claim 3, wherein said shttable member isa lever pivotally mounted at one end on the trame for longitudinalswinging movement about a ransverse anis and the connection between saidspring means and said lever includes a pin carried Iby said spring meansand a slot @provi-ded in the other end of lsaid lever slidably receivingsaid pin.

5. The invention set forth in claim 2, wherein the pivotal connectionbetween said standard and said :upright member includes a longitudinallyextending slot formed in the upright member and a pin carried by sa-idstandard and slidable in said slot to accommodate rearward movement ofsaid standard in response to abnormal draft forces acting .on said tool.

6. ln a cushion spring trip assembly for an implement having asupporting frame, a standard having an earth working tool at its lowerend, longitudinally spaced pivot elements carried by the frame,complementary pivot elements carried by forward and rearward portions.of said standard and cooperative with the pivot elements on the trameto provide longitudinally spaced pivot means connecting the standard tothe frame, `reans in the connection ot the standard to the trameaccommodating longitudinal movement of the standard relative to theframe, the forwardmost of said pivotal connections between tie standardand the frame including lost motion in a generally vertical planeaccommodating upward movement of the forward portion of the standardabout the rearmost of said pivotal connections prior to saidlongitudinal movement of the standard relative to the frame, rand springbiasing means operatively connected between said supporting frame andsaid standard opposing said upwardly movement of the forward portion yofthe standard.

References Cited by the Examiner UNTTED STATES PATENTS 3,052,308 9/62Quanteck 172-264 FOREIGN PATENTS 519,045 3/40 Greaterimin.' 161,484ll/57 Sweden.

T. GRAHAM CRAVER, Primary Examiner.

